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Updated: Aug 15, 2026

Fine-tuning the Size and Minimizing the Noise of Solid-state Nanopores
Published on: October 31, 2013
The molecular size required varies according to the reaction step round the sodium pump cycle
1Department of Physiology, Leicester University, England.
Abstract:
Progress along the path of the sodium pump cycle requires a stepwise recruitment of additional subunits for maximal activity. These results show that whereas a particle the size of the alpha beta protomer presents Na+,K+-ATPase activity at 10 microM ATP, an additional subunit, perhaps a second alpha-chain, is required to obtain the much greater Na+,K+-ATPase activity resulting from the occupation of low-affinity ATP sites at physiological ATP concentrations. A non-phosphorylating ATP analogue, however, will modestly stimulate the Na+,K+-ATPase activity acting at an alternative low-affinity site or step on the alpha beta protomer.
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